Health Assessment of the Urban Concrete Structures Affected by a Long Flood Using Quick Resistivity Measurements and Other NDTs

Due to the global climate change more frequently floods occur and make the urban infrastructure become more vulnerable. A typical example is with Thailand, where ten years ago a gigantic flooding (named the Tropical Storm Nock-ten) had inundated many cities a lot of urban structures had been submerged in the water for many months. To address their safety a structure health assessment was conducted using core samples taken from the concrete structures aged of 10–35 years old above and below the flood water level at five study sites. This research paper presents a review of the results by this study. Four parameters, i.e., Hammer-Schmidt rebound value, resistivity, compressive strength and effective porosity, were measured both in situ and in the laboratory, all of which were found to be reduced after the flood. The investigation also found that the older concrete structures deteriorated more than the younger ones. A good correlation between concrete resistivity and compressive strength was obtained, suggesting a quick and cost-effective technique using electric resistivity measurements to monitor and assess the health of the flood-affected concrete structures.